MONTHLY, adjective Continued a month or performed in a month; as the monthly revolution of the moon. 1. Done or happening once a month, or every month; as the monthly concert of prayer; a monthly visit. MONTHLY, adverb Once a month; in every month. The moon changes monthly 1. As if under the influence of the moon; in the manner of a lunatic. [Not used.]
Source: Webster's 1828 American Dictionary ↗ · public-domain · returned verbatim, no AI